1. Field of the Invention
The present invention relates to a technology for automatically adjusting the display image of a microscope, and more particularly to a technology for automatically adjusting a display image on the basis of the lightness of the display image.
2. Description of the Related Art
For example, the lightness of an image displayed by a confocal laser fluorescent microscope varies depending on the setting of both the intensity of laser light emitted from a laser light source and the diameter of a confocal pinhole, and the setting of the amplification factor of a detector. Furthermore, the lightness of an image varies depending on a specimen being an observation target. Therefore, when a specimen is observed by a microscope, generally it becomes necessary to adjust an obtained image, which becomes a burden for the user of the microscope. Therefore, a function to automate image adjustment is desired as one function of a microscope.
Japanese Laid-open Patent Publication No. H9-138353 discloses a laser microscope for automatically adjusting the lightness of an image, that is, brightness detected by a detector. This microscope registers the setting of a microscope, for obtaining certain detection brightness in advance and obtains certain lightness of an image by adjusting the laser intensity, the amplification factor of a detector and the like, according to the setting.
However, in the technology disclosed by Japanese Laid-open Patent Publication No. H9-138353, the setting for obtaining certain detection brightness is classified and registered, for example, for each characteristic of a specimen (for example, the luminescence efficiency of a specimen against illumination light, etc.) in advance. Therefore, it becomes necessary to register setting information for each characteristic of a specimen in advance.
As to the calculation method of detection brightness being the target of automatic adjustment, various methods, such as the maximum brightness value, an average value in a screen central portion, a weighted average value (weighted average) and the like are disclosed besides the average value of the entire image. Although the differences of these methods affect the lightness of an image after automatic adjustment, neither their detailed selection criteria nor the setting of parameters (for example, weighted value, etc.) used in the various methods are not referred to.
Basically, the lightness of an image should be determined emphasizing the lightness of a part to be observed in the image. In the case of fluorescent observation by a fluorescent microscope, for example, a cell is a part to be observed. In many cases, a cell to be observed is fairly small compared with the entire screen and the position of the part in the image varies. In order to automatically adjust the image appropriately, it is necessary to obtain the lightness of a part to be observed with high precision taking these into consideration.